The present invention relates generally to a system for delivering abrasive particulate material under pressure, and more particularly to a system which utilizes a pressurized source to fluidize and deliver abrasive particulate material for abrading a surface of another material, such as for abrading a portion of a silicon substrate of an ink-jet printhead to thereby form an ink fill slot in the silicon substrate.
A conventional process, commonly referred to as sandblasting, combines abrasive particulate material, such as sand, with a pressurized source of gas, for example, air, to form an abrasive mixture under pressure and directs the abrasive mixture under pressure at a surface. Such a conventional sandblasting process is typically used for cleaning, polishing, or abrading the surface at which the abrasive mixture is directed. Existing sandblasting systems typically include a storage container adapted to contain the abrasive particulate material therein, and a pressure line through which the pressurized source of gas is directed and into which the abrasive particulate material is fed by gravity flow from the storage container.
More particularly, sandblasting has been employed to form an ink fill slot in a silicon substrate of an ink-jet printhead. Existing sandblasting systems employed for forming the ink fill slot typically rely on gravity flow, vibration of the storage container, and/or modulation of the pressure line to ensure discharge of the abrasive particulate material from the storage container, through a metering orifice, and into the pressure line. The vibration and/or modulation in these existing sandblasting systems, however, results in chaotic behavior, or inconsistent flow, of the abrasive particulate material through the metering orifice. This chaotic behavior resulting when the ink fill slot is formed with existing sandblasting systems is identified by random size and shape variations of the ink fill slot. Since the ink fill slot provides a supply of ink to a printing element of the ink-jet printhead during a printing process, a distance from the ink fill slot to the printing element effects the supply of ink to the printing element. Size and shape variations in the ink fill slot, therefore, can degrade printing performance.
Accordingly, a need exists for a system for delivering abrasive particulate material under pressure which provides consistent flow of the abrasive particulate material from a storage container, through a metering orifice, and into an output pressure line. In particular, there is a need for a method for more uniformly forming an ink fill slot in a silicon substrate of an ink-jet printhead.
One aspect of the present invention provides a method of abrading a portion of a silicon substrate. The method includes fluidizing abrasive particulate material with a first gas within a storage container, combining the gas fluidized abrasive particulate material with a stream of a second gas to provide a stream of the gas fluidized abrasive particulate material, and directing the stream of the gas fluidized abrasive particulate material at the silicon substrate to abrade the portion of the silicon substrate.